Using WP_Customize_Image_Control and can no longer upload/select images

Hi guys,

I’m working on a theme with multiple sections, around 4 or 5 and each of them has a background image. I’m using the customizer API to select background images for my sections.

The problem that I encounter is that when I instantiate a WP_Customize_Image_Control object like in the code below, as long as my theme is active, I can no longer select or upload any image, whether it’s from the customizer menu or when editing a post, setting a featured image or whatever.

Here’s the code I got from codex and I’m having trouble with:

$wp_customize->add_setting( 'heading_bgimage',
		array(
			'default' => '',
			'type' => 'theme_mod',
			'capability' => array('edit_theme_options', 'upload_files', 'edit_files'),
			'transport' => 'postMessage',
		)
	);

	$wp_customize->add_control(new WP_Customize_Image_Control(
			$wp_customize,
			'heading_bgimage',
			array(
				'label'      => __( 'Upload an image', 'chef' ),
				'section'    => 'chef_options',
				'settings'   => 'heading_bgimage',
				'context'    => 'my_theme_name'
			)
		)
	);

I suspect that there’s something related to the context, changed it but to no avail…

1) Are there any other arguments I should provide to the WP_Customize_Image_Control constructor to have access to all the other already uploaded images and be able to upload images with it?

2) The error that I get when I try to upload an image is
"An error occurred in the upload. Please try again later".
I looked at async-upload.php and it outputs:

{"success":true,"data":{"id":31,"title":"2","filename":"2-2.jpg","url":"h...

so it looks like the upload works and there’s something else. It would be useful some info to at least further debug on what’s happening…

Thanks!